Hello -

        I have been thinking about the issue of a 'unique identifier' for
a METS object and I am a bit confused. In the OAI protocol spec, a clear
distinction is drawn between the unique identifier required by OAI, and
the object identifier (section 2.3 of the protocol).
        The unique identifier clearly pertains to the repository, that is,
it is what is used by the repository to identify the object. So that makes
me wonder why Herbert van de Sompel is concerned about the object
identifier in the METS scheme.
        What does confuse me, though, is what one would put in the Dublin
Core field that is used to refer to the underlying material, since METS
allows a document to exist as pieces tied together by the METS object.
Would you put in 'a unique identifier for the METS object'? and if so,
wouldn't a unique identifier in the OBJID attribute be a requirement of
METS' internal logic?


Garey Mills
Library Systems Office
UC Berkeley